title: Molecular analysis of the UV-inducible pili operon from Sulfolobus acidocaldarius.
abstract: Upon ultraviolet (UV) stress, hyperthermophilic Sulfolobus species show a highly induced transcription of a gene cluster responsible for pili biogenesis: the UV-inducible pili operon (ups operon). This operon is involved in UV-induced pili assembly, cellular aggregation, and subsequent DNA exchange between cells. As the system increases the fitness of Sulfolobus cells after UV light exposure, we assume that transfer of DNA takes place in order to repair UV-induced DNA damages via homologous recombination. Here, we studied all genes present in the ups cluster via gene deletion analysis with a focus on UpsX, a protein that shows no identifiable functional domains. UspX does not seem to be structurally essential for UV-induced pili formation and cellular aggregation, but appears to be important for efficient DNA transfer. In addition, we could show that pilin subunits UpsA and UpsB probably both function as major pilin subunits in the ups pili.
authors.affiliation: Molecular Biology of Archaea, Max Planck Institute for terrestrial Microbiology, Karl-von-Frisch-Strasse 10, 35043, Marburg, Germany.
authors.forename: Marleen
authors.initials: M
authors.lastname: van Wolferen
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Ajon
authors.forename: Arnold J M
authors.initials: AJ
authors.lastname: Driessen
authors.forename: Sonja-Verena
authors.initials: SV
authors.lastname: Albers
mesh_terms: D001692:Biological Transport; D004252:DNA Mutational Analysis; D004269:DNA, Bacterial / Q000378:metabolism; D036781:Fimbriae Proteins / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000235:genetics* / Q000378:metabolism*; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial / Q000528:radiation effects*; D009876:Operon; D016945:Sulfolobus acidocaldarius / Q000235:genetics* / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D036781:Fimbriae Proteins
keywords: Archaea; DNA exchange; conjugation; type IV pili